RRUs are often used in outdoor, and thus IP55/65 should be fulfilled. There are many external interfaces, and these interfaces also need to be designed to fulfill the IP55/65 or more stricter requirements. For current products, there are two solutions available in the market. With referring to FIG. 1a, one solution is an outdoor connector 300. As shown in FIG. 1b, the other solution is an interface chamber 400.
It is well known in the art that the solution using the outdoor connector 300 is very expensive, though it can reduce the size of the obtained product. The outdoor connector 300 also needs a big area of a front panel, because an operation space should be kept between connectors. The operation space also should be kept for IP protection between the connector and a frame of the product.
With respect to the other solution, using the interface chamber 400 is cheap, because standard indoor connectors are used and IP protection is designed in the frame of the product and cable sealing is combined with a gasket. However, more space should be kept for cable routing, and thus it would lead to bigger size of the product. Further, this solution has another drawback that it will lead to water leakage in site due to being unreliable.